Modular platforms are used in a variety of applications, including but not limited to enterprise servers, telecommunication servers, flexi-servers and mass storage servers. Many of these applications may have one or more specifications that may govern various physical specifications and operating parameters of the modular platform and how components (e.g., boards, modules, backplanes, air plenums, etc.) are configured within or coupled to the modular platform. One such specification is the PCI Industrial Computer Manufacturers Group (PICMG), Advanced Telecommunications Computing Architecture (ATCA) Base Specification, PICMG 3.0 Rev. 1.0, published Dec. 30, 2002 (hereinafter referred to as “the ATCA specification”).
The ATCA specification provides design criteria for modular platforms to serve as carrier grade communication equipment. This design criterion may include, but is not limited to, configurations for such components as intake/exhaust plenums, fan modules, power entry modules, boards and backplanes. Design criteria may also include configurations to couple components such as a rear interface unit (hereinafter referred to as a “rear transition module” or “RTM”) to other components such as a board.
The ATCA specification also provides design criteria which constrain a modular platform to certain dimensional requirements, such as height, width and length. These constraints may impact the air flow and the consequent cooling of a modular platform. For example, to meet these constraints, modular platform components (e.g., power entry modules and/or fan modules) may be placed towards the lower part of the modular platform. Typically, backplanes designed in compliance with ATCA may only enable this type of component placement. However, since the lower part of the modular platform may include an air plenum to improve air flow and air flow is negatively impacted by this component placement, backplanes designed this way may be problematic.